Good correlations exist between condition and the amount of fat, protein and water present in young Tilapia rendalli, but extreme care must be exercised when determining the nature of these relationships. The use of percentages when expressing the amounts of each component should be avoided because such analyses can lead to erroneous results. Similarly the often used fat-water relationship for predicting the fat content in fish should not be used as this also leads to erroneous results. The reasons for the poor relationships are discussed and methods for overcoming these problems are given.
A reappraisal of oxygen uptake by Sarotherodon mossambicus was undertaken using a continuous flow respirometer. Measurements were obtained over the temperature range 16" C-37" C for fish weighing between 10 g and 150 g. Oxygen uptake was converted to energy equivalents (Q,,) using the value 13.68 J mg O,-l and the routine metabolic energy expenditure can be described by the equation E=0.0086 t2'0783 Mo'662 where E is the energy requirement for routine metabolism expressed in J h -l , t the temperature in "C and M the mass in g.
Using a continuous flow respirometer it was shown that young Tilapfa rendalli had three distinct phases of oxygen consumption over the temperature range of 1740" C. In the first phase (17-28" C) the metabolic energy demand followed the normal logarithmic increase with increasing temperature. Between 28 and 37" C the increased oxygen uptake was suppressed and showed a relatively small increase with increasing temperature. This feature was believed to be a significant energy saving function important to the growth of these fish which feed in the warm eulitoral margins of lakes during the day. The final phase shows a return to the original logarithmic increase in oxygen consumption. These results were related to, and compared with, actual changes in biomass at various temperatures and the theoretical and actual biomass changes were found to compare favourably.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.